Bioremediation of Crude Oil-Contaminated Soil in the
Presence of Nickel, Zinc and Cadmium Heavy Metals Using Bacterial and Fungal
Consortia-Bioaugmentation Strategy

Abstract:The study evaluated the effectiveness of
indigenous bacterial consortia (Pseudomonas aeruginosa, Bacillus
subtilis and Micrococcus letus) and fungal consortia (Aspergillus
niger, Aspergillus carmari and Penicillium notatum) as well as
their combination (bacterial-fungal consortia) as bioaugmentation agents in the
soil bioremediation of petroleum hydrocarbons in the absence and presence of
nickel, zinc and cadmium heavy metals. Bioremediation was carried out in 10% w/w
crude oil-contaminated soil microcosms for 35 days in the absence and presence
of nickel, zinc, and cadmium bioaugmented with or without bacterial, fungal and
bacterial-fungal consortia, respectively. In the heavy metal-free soil
microcosms, 72.5%, 64% and 90.7% total petroleum hydrocarbon (TPH)
biodegradation were attained with bacterial, fungal and bacterial-fungal
consortia, respectively, while 45% TPH biodegradation was achieved in the non-bioaugmented
soil microcosm. In the heavy metal-soil microcosms: nickel, zinc, cadmium and
mixed form (nickel + zinc + cadmium), 79.2%, 81.4%, 75.3% and 68.2% TPH
biodegradation was correspondingly obtained with bacterial consortia; 69.4%,
66.4%, 68.2%, and 60.6% with fungal consortia; while 99%, 98.5%, 95.7%, and 100%
was respectively attained with bacterial-fungal consortia. The kinetics of TPH
biodegradation were adequately described by the first-order kinetics and
half-life times were estimated. Soil microcosm bioaugmented with
bacterial-fungal consortia displayed the highest biodegradation rate constant
with the lowest half-life times in the absence and presence of heavy metals.
Therefore, the results suggest that microbial consortia (bacterial and fungal)
could be very effective for soil bioremediation of crude oil in the presence of
heavy metals.

Abstract: This study evaluated
the activities of crude, acetone and ethanolic extracts of Capsicum
frutescens var. minima
fruit against
Anopheles gambiae
larva. The bioassay was carried out for 24 hours using Anopheles gambiae
larva obtained from the wild. The Anopheles gambiae
was identified following standard protocol. Results showed that the mortality
rate increased statistically at p<0.05 as the concentration of the plant
extracts increased. The ethanolic, acetone and crude extracts had LC50
value of 115.24 ppm, 173.16 ppm and 265.19 ppm respectively, being apparently
different. The efficacy of the Capsicum frutescens var. minima
fruit were in the order aqueous < acetone < ethanol. Based on the findings of
this study, there is the need for research to focus on the isolation and
purification of the exact bioactive ingredients that enables Capsicum
frutescens var. minima fruit confers insecticidal potentials.

Food Engineering as a Potential Solution for Mitigating of
the Detrimental Effects of Livestock Production

Abstract:
Global
demand for meat is on the rise. Increase in livestock production is the first
but not the best solution to supply this demand. Livestock production leads to
an increase in the greenhouse gasses, causing global warming and climate change,
which also has a negative impact on the livestock breeding. Thus, scientists
have concentrated on the production of in vitro-engineered meat which
could be tasty, healthy and environmental friendly to substitute livestock meat.
In this article, the environmental impacts of livestock production system on the
climate change, water quality and public health are discussed, and then the
artificial meat production technology, its benefits, challenges and consumer’
sreactions are reviewed.

Mechanical Properties and Swelling Behavior of Acrylamide
Hydrogels using Montmorillonite and Kaolinite as Clays

Abstract: In this study in order to increase
the release ability of acrylamide hydrogels, modified acrylamide-based hydrogel
nanocomposites were synthesized. The aim of this research was to evaluate the
swelling ratio of hydrogel with the best clay, to reach the highest rate of
swelling. To enhance the swelling ratio of hydrogels, the clays were applied in
their structure. Amongst the applied clays in the structure of the hydrogels,
montmorillonite was found to be more effective than kaolinite. Further using
conventional techniques such as X-ray diffraction (XRD) and Energy Dispersive
X-Ray (EDX) performed the characterization of the clays, while the hydrogels
were characterized by Fourier Transform Infrared Spectroscopy (FTIR), Field
Emission Scanning Electron Microscope (FESEM), and EDX. The XRD analysis of
clays showed that there is a different amount of carbon, oxygen, sodium,
calcium, magnesium, aluminum, silicon, potassium and iron. The amount of oxygen
in montmorillonite was 42.12 however, the amount of oxygen in kaolinite was
2.01. The XRD pattern of montmorillonite including a peak relevant to the basal
dividing of (2θ = 7.83°) 11.28 Ĺ was verified. In the acrylamide/montmorillonite
hydrogels, this peak was shifted to a lower point of the angle, comparing to the
basal spacing of (2θ = 6.40°) 13.78 Ĺ and (2θ = 6.24°) 14.11 Ĺ. Such an increase
in the basal spacing oblique that the monomer was inserted into the interlayer
of the clay.

Abstract:
The elucidation of soil residual hydrocarbon (SRH) in oil-impacted dumpsite
soils is aimed at distinguishing the principal source (municipal waste dumpsite
or oil well-head clusters) of petroleum and polycyclic aromatic hydrocarbons in
the mangrove environment receiving mineral oil loading form mixed anthropogenic
influences. Chemical fingerprints of soil specimen were obtained on
determination by gas chromatographic – flame ionization detection (GC-FID)
technique using an HP 5890 series II instrument. Flt/Pyr ratios revealed the
presence of petrogenic hydrocarbons while carbon preference index (CPI) showed
soils composed mainly of degraded material and fossil fuels, apart from location
E-2 which was loaded with non-biodegraded biological materials using Ph/nC18
data. Elucidation of Pr/nC17 ratios showed that the retention of non-biodegraded
hydrocarbon was decimated at locations E-4 and E-6 due to reduced microbial
degradation in comparison to the other field areas. Overall, the soil was
insignificantly impacted by terrestrial sources, as greater magnitude came from
surrounding oil well clusters. Therefore, soil toxicants are likely to be
bio-accumulated in crops growing along proximate farmlands, especially nypa palm
fruits which are commonly consumed. It is imperative to avoid ingesting herbage
or other nutriments from this area until residual oil seepages are effectively
controlled and hydrocarbons have been monitored for substantial degradation.

Treatment of Dye Wastewater by Functionalization of
Bentonite-Methylene Blue with Sodium Persulfate

Abstract:
Bentonite has been effectively used in many studies for the removal of methylene
blue (MB) laden waste waters. This is due to its high swelling ratio, good
adsorptive properties and environmentally friendly characteristics. In spite of
this, prolonged use renders the BMB non-functional and cause for discard. Sodium
persulfate (SPS), has been reported to be an excellent flocculating agent for
the functionalization of spent adsorbent due to some of its unique properties.
In this study, the functionalization of spent bentonite-methylene blue (BMB)
adsorbent in dye wastewater treatment was carried out using SPS at varying
temperature conditions. Results revealed that the addition of SPS to MB-loaded
adsorbent demonstrated efficient adsorption, high flocculation efficiency as
well as faster equilibrium (60 min).
The BMB loaded adsorbent
showed
95% removal efficiency up to three cycles. A plausible mechanism was proposed
and discussed on the basis of the results. Thus, exhausted
BMB was found to be effectively used
for treatment of coloured wastewater on an industrial scale.